KMPCL_6í-600MW_DCS_FSSS_Writeup_R1.1

KSK Mahanadi Power Company Limited

6 x 600 MW Thermal Power Project Nariyara, Chhattisgarh,India

DCS FSSS Write up

DOCUMENT NO: xxxxxx-xx

REV. NO. R 1.1

DEVELOPMENT CONSULTANTS PRIVATE LIMITED CONSULTING ENGINEERS MUMBAI , INDIA

SEPCO ELECTRIC POWER CONSTRUCTION CORPORATION. Jinan,China

NORTHEAST ELECTRIC POWER DESIGN INSTITUTE Changchun,China

Emerson Process Management Power&Water Solution(Shanghai) CO., LTD

DCS FSSS WRITE UP

6 x 600 MW KSK Mahanadi

Thermal Power Project

DOCUMENT NO.: xxxxxx-xx

Rev. 1.0 Page 2 of 74

EMERSON

DOCUMENT CONTROL SHEET

PROJECT :

6 X 600 MW KSK Mahanadi Thermal Power Project

CLIENT :

KSK Mahanadi Power Company Limited

DOCUMENT TITLE :

DCS FSSS Write up

DOCUMENT NO. :

xxxxxx-xx

REV. NO. :

1.1

ENDORSEMENTS :

1.0 28-1-11 First Issue

Initials Sgn. Initials Sgn. Initials Sgn. Initials Sgn.Rev No Date Description Prepared by Reviewed by Approved by Issue Authorization

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Contents

1. GENERAL ....................................................................................................................3 1.1. Purpose of Document ....................................................................................3

2. DEFINITIONS & ABBREVIATIONS .........................................................3 2.1. Definitions ........................................................................................................3 2.2. Abbreviations .......................................................................................................3

3. SYSTEM OVERVIEW ........................................................................................3 3.1. Hardware Configuration ...............................................................................3 3.2. Software Function .........................................................................................3 3.3. Hardwired Exchange Signal ..............................................................3

4. Master Fuel Trip ................................................................................................3 4.1.1. MFT Conditions MFT ........................................................................3 4.1.2. MFT Reset Conditions MFT .................................................................3 4.1.3. Actions after MFT MFT .............................................................................3

4.2. Oil Fuel Trip .............................................................................................3 4.2.1. LDO OFT Conditions LDOOFT ........................................3 4.2.2. HFO OFT Conditions HFO ...................................................3

5. Common Control Logic ................................................................................3 5.1. Common Control Logic Overview ...............................................3 5.2. Fuel Oil Leak Test .....................................................................................3

5.2.1. LDO Leak Test Procedure LDO .........................................3 5.2.2. HFO Leak Test Procedure HFO .........................................3

5.3. Furnace Purge ................................................................................................3

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5.3.1. Furnace Purge Permissive Conditions ...................................3 5.3.2. Furnace Purge Procedure ...............................................................3

5.4. Oil Fuel Ignition condition ...............................................................3 5.4.1. LDO Ignition Conditions LDO .....................................3 5.4.2. HFO Ignition Conditions HFO ......................................3

5.5. Oil Shutoff Valve logic .....................................................................3 5.5.1. LDO Supply Oil Shut-off Valve LDO .......................................3 5.5.2. HFO Supply Oil Shut-off Valve HFO .......................................3 5.5.3. LDO Return Oil Shut-off Valve LDO ...............................3 5.5.4. HFO Return Oil Shut-off Valve HFO................................3

5.6. Flame Detector Cooling Air Fan ..........................................................3 5.6.1. Flame Detector Cooling Air Fan A A...........................................3 5.6.2. Flame Detector Cooling Air Fan B B...........................................3

6. FUEL OIL CONTROL LOGIC ............................................................3 6.1. LDO Control Logic ..................................................................3

6.1.1. LDO Layer Control(e.g. BC) ( BC )..........................................3 6.1.2. LDO Coupling Control .....................................................3 6.1.3. LDO Single Control (e.g. BC1) LDO BC1 3

6.2. HFO Control Logic ..................................................................3 6.2.1. HFO Layer Control (e.g. AB) HFOAB ............3 6.2.2. HFO Coupling Control ...................................................3 6.2.3. HFO Single Control (e.g. AB1) HFO AB1 3

7. COAL-FIRED CONTROL LOGIC .............................................................3 7.1. Coal Ignition Condition ............................................................................3

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7.2. Coal Layer Ignition Energy Requirement ....................................3 7.3. Coal Layer Sequence Control .......................................................................3

7.3.1. Coal Layer A Sequence start procedure A .............................................3 7.3.2. Coal Layer A Sequence stop procedure A ..........................................3

7.4. Pulverizer Lube Oil Pump ................................................................3 7.5. Pulverizer Lube Oil Box Heater A ......................................3 7.6. Pulverizer A A ..................................................................................................3

7.6.1. Pulverizer A Trip Condition A .................................................3 7.6.2. Pulverizer A Start permission A ..............................................3

7.7. Coal Feeder A A ...............................................................................................3 7.8. Pulverizer A Inlet Cold Air Damper A ........................................3 7.9. Pulverizer A Inlet Hot Air Damper A ..........................................3 7.10. Pulverizer A Outlet Damp A ................................................................3 7.11. Pulverizer A Sealing Air Damp A ...................................................3 7.12. Pulverizer A Inerting Steam Inlet Valve A ..........................3 7.13. Coal Feeder A Inlet Valve A ................................................................3 7.14. Coal Feeder A Outlet Valve ............................................................................................3

7.15. Coal Feeder A Sealing air Damp A .................................................3 7.16. Run Back ........................................................................................................................3

7.16.1. Actions after RB RB ......................................................................................3 7.16.2. RB Reset Condition RB ........................................................................3

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1. GENERAL

1.1. Purpose of Document

This FSSS write up define the function specification of the FSSS control system for the

KSK 6*600MW power Project. KSK 6*600MW FSSS

This document outlines the FSSS hardware design and describes the control, interlock

logic and operation of the FSSS. FSSS

2. DEFINITIONS & ABBREVIATIONS The following definitions and abbreviations shall apply for use in this specification.

2.1. Definitions EMERSON EMERSON Power&Water Process CO., LTD Third Party Third party / Foreign Device supplier not within

Emersons scope of supply End user KSK Mahanadi Power Company Limited. Others Scope not within EMERSONs Supply Field Equipment that is external to the DCS cabinets

2.2. Abbreviations FSSS Furnace Safeguarding and Supervisory System CCS Coordination Control System MFT Master Fuel Trip MCR Maximum Continuous Ratings OFT Oil Fuel Trip DCS Distributed Control System

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LDO Light Diesel Oil HFO Heavy Fuel Oil LCD Liquid Crystal Display SCS Sequence Control System TV Throttle Valve GV Governor Valve RSV Reheat Stop Valve IV Intercept Valve CV Control Valve RB Run Back SIL Safety Integrity Level BFPT Boiler feedwater pump turbine

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3. SYSTEM OVERVIEW

3.1. Hardware Configuration

The Furnace Safeguarding and Supervisory System (FSSS) is part of the total plant DCS system. Since MFT plays a crucial role in preventing operator-made accident and boiler explosion due to device malfunction, it is the indispensable automation systemTMR for safe boiler operation in large power plant. FSSS DCSMFT

In KSK power project, ONE TMR Controller for MFT, Three Emerson Ovation Controller for FSSS Device management.

Controller Description TMR

(ICStriplex advance) MFT

CTRL01 (Emerson OCR400)

HFO AB, LDO BC, Pulverizer A/B Line Scan Fan A , Pulverizer Sealing A LDO Trip/Return Valve. AB BC A/B , A A


HFO CD,LDO EF,Pulverizer C/D LineScan Fan B,Pulverizer Sealing Fan B CD EF C/D B B


HFO FG,Pulverizer E/F/G Line

FG E/F/G The MFT processing functions implemented in TMR controller .The function is all

critical for safe boiler operation, so the Safety Manager is used for TMR controller. Safety

Manager is a safety solution designed to protect safety-critical processes from runaway

situations, and allows the system to comply with SIL3. For the detailed information about

Safety Manager please refer the Hardware ICStriplex Aadvance Safety Manager

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MFT TMR TMR SIL3 ICStriplex Aadvance

Three ovation controller implements other fsss control. For the detailed information

about ovation OCR400 refer the document Hardware

OVATION FSSS OVATION OCR400

MFT trip relay cabinet is used in KSK 6*600MW power project for boiler trip (protection);

only relays and hardwired connection exist in this cabinet. If the MFT trip relay is activated,

all fuels supply will be shut-off to protect the boiler, and the MFT signal will be sent to other

relevant system immediately. MFT KSK 6*600MW MFT MFT

For the boiler emergency shutdown system two set of hardwired emergency pushbutton

and trip relays are provided. In case of rare DCS system failure or no any response on

station LCD, operator can press the emergency pushbutton on console desk to directly

activate the MFT relays. DCS MFT

MFT trip relay cabinet is redundant design Loop, two set of MFT relays are mounted in this

cabinet, and every set of the MFT relays independent 220VDC power supply is used.

These two set of MFT relay hardwired loops adopt separate input signal, its relays output

are connected together at the terminal in this cabinet, and provide one output to field for

devices MFT protect trip. MFT MFT MFT 220VDC

Totally XX relay outputs are designed for one set of MFT. Please refer the document DCS

MFT Cabinet for the detailed MFT trip relay cabinet drawing MFT XX MFT

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3.2. Software Function

The FSSS software can be divided into three part functions: MFT control logics, common

control logics,Fuel oil control logics and Coal-fired control logics.

In KSK power project , based on the function important levels and the good engineering practice, MFT Control logic is implemented in ICStriplex Aadvance controller. Common control logics and Fuel oil control logics and Coal-fired control logics are

implemented in OCR400 controller

FSSS MFT MFT ICStriplex Aadvance OCR400

The Common control logic also include the control of the common used FSSS device as

cooling air fan, fuel oil shut-off valve etc.

FSSS

Fuel oil control logic includes the oil burner start/stop control, coupling and layer start/stop

control.

Coal-fired control logic includes all seven layers pulverizer system sequence control and

the single device interlock control like coal feeder, pulverizer and its relevant damp.

As the part of DCS, the major FSSS operator interface is through station LCDs graphic.

DCS FSSS LDC

3.3. Hardwired Exchange Signal

As per the Customers requirement, Safety manager is used for boiler critical protection.

All Signals between DCS and ICStriplex Aadvance controller will not use peer-to peer

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communication, and the hardwired connection is designed to acquire the higher system

reliability.

DCS ICStriplex Aadvance

The following is the hardwired exchange signal list :

Drum level high II (1) 1 Drum level low II (1) 1 Drum level high II (2) 2 Drum level low II (2) 2 Drum level high II (3) 3 Drum level low II (3) 3 Total air flow low (1) 1 Total air flow low (2) 2 Total air flow low (3) 3 Both APH stopped(1) 1 Both APH stopped(2) 2 Both APH stopped(3) 3 Boiler ignition fail(1) 1 Boiler ignition fail(2) 2 Boiler ignition fail(3) 3 All fuel loose(1) 1 All fuel loose(2) 1 All fuel loose(3) 1 All flame loose(1) 1 All flame loose(2) 2

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All flame loose(3) 3 Feedwater flow low(1) 1 Feedwater flow low(2) 2 Feedwater flow low(3) 3 All Feed water pump stopped 1 1 All Feed water pump stopped 2 1 All Feed water pump stopped 3 1 Super heater outlet temperature high(1) 1 Super heater outlet temperature high(2) 2 Super heater outlet temperature high(3) 3 Re heater outlet temperature high(1) 1 Re heater outlet temperature high(2) 2 Re heater outlet temperature high(3) 3 Re heater Lost protection1 1 Re heater Lost protection2 2 Re heater Lost protection3 3 PULVERIZER SERVING & NO OIL GUN SERVING1 PULVERIZER SERVING & NO OIL GUN SERVING2 PULVERIZER SERVING & NO OIL GUN SERVING3 UNIT LOAD >50%(1) >50%(1) UNIT LOAD >50%(2) >50%(2) UNIT LOAD >50%(3) >50%(3) MFT RESET 1 MFT 1 MFT RESET 1 MFT 2

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For the detailed information about DCS and ICStriplex Aadvance controller echange IO refer the document KSK Unit#1 DCS IO Assignment

4. Master Fuel Trip Master Fuel Trip (MFT) is the key content of the boiler protection, and also is the most

important safety function of FSSS. On any dangerous situation which will keep boiler from

safe operation occurs, MFT will fast cut off all the fuel oil and coal feeder to make the boiler

in safety status, avoid or limit the accident.

MFT FSSS

MFT

MFT logic has the function of the first out trip condition memorize, it can record the first

occurred condition when MFT activate. The first out alarm will be cleared after MFT Reset.

MFT MFT

4.1.1. MFT Conditions MFT The following conditions will cause MFT:

Both of the two emergency shutdown buttons are pressed by operator; 2 MFT

Furnace pressure is above high value II3240Pa, two of three hardwired input from field with 2 second on delay;

3240Pa 2s Furnace pressure is below low value II2490Pa, two of three hardwired input from

field with 2 second on delay;

2490Pa 2s

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Boiler drum level is above high value II250mm, two of three hardwired input from CCS system with 5 second on delay;

250mm CCS 5s

Boiler drum level is below low value II-300mm, two of three hardwired input from CCS system with 5 second on delay;

(-300mm) CCS 5s

Boiler Feed water flow is below xx t/h, two of three hardwired input from CCS with 5 second on delay;

XXt/hCCS 5s;

All feed water pumps stopped, two of three hardwired input from field with 2 second on delay;

2s

All boiler water cycle pumps stopped, two of three hardwired input from field with 2 second on delay;

2s

Both of the forced draft fans are stopped;

Both of the induced draft fans are stopped;

Both of the air pre heaters are stopped;

Flame detector scan air header pressure is below low value II, two of three hardwired input from field with 30 second on delay;

30s

Turbine tripped on generator load great than 50%, two of three hardwired input from ETS;

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>50

Boiler total air flow is below 25%, two of three hardwired input from CCS with 3 second on delay;

20%:

a) Turbines either all TV or all GV closed and Both HP bypass CVs are closed.

2 4 2

b) Turbines either all RSV or all IV closed and Both LP bypass CVs are closed.

2 2 2

Ignite fail protection, includes two conditions as following, any condition will trigger this protect:

a) After MFT reset (initial ignition permit) and the LDO supply oil shut-off valve has

opened, no any LDO oil gun is running during 10 minutes

(LDO) MFT ()10

b) After MFT reset, three times of oil gun ignition failed.

MFT 3

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Loss of all fuel, all the following conditions and with Any Oil Burner Running memorize will trigger this protection.

a) All twelve HFO burners oil valve closed or HFO header oil cut off valve closed

b) All LDO burners oil valve closed or LDO header oil cut off valve closed

c) All seven pulverizers stopped

Loss of all flame, all the flowing conditions with 3 second on delay and with Coal Burner Running memorize will trigger this protection. Normal stoppage of the boiler will

not trigger MFT.

3s MFT

a) No flame detected for all oil burners;

b) No 3/4 flame detected for all pulverizer layers;

3/4

Both of the primary air fans are stopped during any coal layer in service but no fuel oil layer running will cause the MFT. 2 Both DCS supply power loose ,the function will be implement in MFT hardwire panel.

two of three hardwired input from DCS supply power cabnet.

DCS

All Boiler recycle pumps stopped

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4.1.2. MFT Reset Conditions MFT MFT will be auto reset under all the following conditions effect:

MFT MFT Furnace purge complete

No MFT Relay Trip exist MFT

No any MFT trip conditions exist MFT

ICStriplex Aadvance controller worker normal ICStriplex Aadvance

MFT Relay trip panel power MFT

4.1.3. Actions after MFT MFT On occasion of any MFT conditions coming, the following steps will be executed:

MFT

Activate the MFT trip relay MFT

Trip all fuel oil burners, this includes

a) Retract all oil gun directly (no oil gun post purge);

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b) Prohibit oil gun ignition;

c) Close all burner oil valves and atomizing valves

d) TO CORNER LOCAL PANEL

MFT[]

Close all Fuel oil supply shut-off valves []

Trip all pulverizers []

Trip all coal Feeders []

Close all pulverizer outlet dampers

Trip both Primary Air Fans []

Trip BFPT ABFPT B AB[]

Close Superheated Steam de-superheating water isolation MOV

Close Reheated Steam spraying water isolation MOV

Set all auxiliary SA damp to purge position

Send the hardwired signal to DCS, ETS, Bypass, and Soot blowing system,ESP system

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MFT DCS(1-9)ETS[]

Reject Forced air and Induced air PID controller to manual mode. If MFT activated by FDF, IDF, or APH both tripped then the running FDF and IDF should tripped immediately

and set the boiler at natural draft status 60 seconds later.

MFT1min,15min

MFT is designed as two redundant loops: software interlock and hardware interlock loop.

At normal condition when MFT coming, the software logic will stop the relevant device by

DCS DO channel, and the MFT trip relay cabinet will also send a hardwired trip signal to

these devices. For example, the fuel oil supply shut-off valve will receive two close

command from separate panel when MFT.

MFT MFT DCS MFT MFT

If DCS is not working, operator also can stop these MFT hardwired device through

hardware interlock loop by pressing the emergency button.

DCS MFT MFT

4.2. Oil Fuel Trip

Oil fuel trip (OFT) logic inspects the fuel oil parameters. On any dangerous situation which

will keep boiler from safe operation occurs, OFT will fast cut off the running oil burners and

close the oil supply shut-off valve.

OFTOFT

FSSS continuously supervise the OFT conditions and will trigger the OFT if any of the

condition occurs. The first OFT condition will be memorized and alarming on station LCD,

the first out condition will reset by OFT reset signal.

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FSSSOFTFSSSOFTOFTOFT

4.2.1. LDO OFT Conditions LDOOFT Any of the following conditions will cause LDO OFT:

(LDO)OFT ()

MFT; MFT

LDO supply oil pressure below low II value with 5 second on delay 5s

LDO instrument air header ressure below low II value with 15 second on delay 15s

LDO OFT will be reset under all the following conditions effect:

(LDO)OFT

No any LDO OFT conditions exist; OFT

LDO supply shut-off valve closed

All LDO burner oil valves closed

LDO oil leak test complete

The actions after LDO OFT:

OFT

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Tripping of all LDO burners, but purge valves will not close, and will start the post purge process if MFT does not happen simultaneously;

(LDO)MFTOFTMFT

Close the LDO supply shut-off valve (LDO)

4.2.2. HFO OFT Conditions HFO Any of the following conditions will cause HFO OFT:

(HFO)OFT

MFT; MFT

HFO supply oil pressure below low II value with 5 second on delay 5s

HFO atomizing steam pressure below low II value with 15 second 15s

HFO Steam temperature pressure below low II value with 15 second 15s

HFO OFT will be reset under all the following conditions effect:

(HFO)OFT

No any HFO OFT conditions exist; (HFO)OFT

HFO supply shut-off valve closed (HFO)

All HFO burner oil valves closed (HFO)

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HFO oil leak test complete

The actions after HFO OFT:

(HFO)OFT

Trip all HFO burner, but the burner atomizing valve and purge valve will not be closed, and will start the post purge process if MFT does not happen simultaneously;

MFT OFT MFT

Close the HFO supply shut-off valve (HFO)

5. Common Control Logic

5.1. Common Control Logic Overview

The common control logic include oil leak function, boiler purge function and auxiliary

FSSS device control, and the interface of DCS with other systems. The detailed function is

as following:

FSSS DCS

1. Ensures no oil will leak in fuel oil supply pipe by executing the fuel oil leak test

procedure.

2. Ensures furnace purge success and no any fuel stored in furnace before boiler ignites

3. Establish the ignition condition including LDO ignition permission, HFO ignition

permission. Forbid oil layer to start before all relevant oil ignite permissions are satisfied.

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LDO HFO

4. Control the auxiliary devices of FSSS like fuel oil shut-off valve, cooling air

fan,Pulverizer sealing air fan.

FSSS

5.2. Fuel Oil Leak Test

The Fuel Oil Leak test logic is designed to prevent the fuel oil leak from supply oil pipeline

(include leak to furnace). The test will be performed to check whether fuel oil leakage is

there between the fuel oil supply shut-off valve and all burner oil valves.

In KSK power project, fuel oil system includes Light Diesel Oil system (LDO) and Heavy

Fuel Oil system (HFO), these two fuel oil system should be performed the oil leak test

separately. Operator can send the LDO/HFO fuel oil leak test start command on LCD

graphics. If the test is confirmed to be unnecessary, it could be by-passed, but this is not

recommended for safe boiler operation.

LDO is available only in the BCEF layer, and HFO is available in the AB, CD, and FG layer.Fuel oil leak test succeed is one of the furnace purge permit conditions.

(LDO)(HFO) CRT (LDO)(HFO)

5.2.1. LDO Leak Test Procedure LDO The following is the LDO leak test permissive conditions:

(LDO)

MFT activated, or MFT reset but any coal layer is in service [MFT ][ MFT ]

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LDO Supply oil pressure normal

LDO supply oil shut-off valve closed

All LDO burner oil valves closed (LDO)

After all the conditions has been satisfied, the message LDO Leak Test Permit will be

displayed on station LCD, operator can push the button labeled with start LDO Leak Test

on LCD to start the test. When the test demand output, the logic will close LDO return

header shut-off valve, send the bypass command to MFT hardwired trip relay for LDO

supply shut-off valve, open the LDO supply shut-off valve and LDO supply oil pressure

adjust CV and the message LDO Oil Leak Test in Progress will be displayed on station

LCD. The following procedure will be started:

CRT (LDO) CRT

(LDO)(LDO) MFT (LDO)

(LDO) CRT

1. Opening of LDO supply oil shut-off valve to fill the oil into header pipeline, and it will be

closed after 60 Second when the oil pressure before LDO return valve is greater than 25

bar. If the filling oil pressure could not reach 25bar during 60 second after the supply

shut-off valve opened, the message Fill Oil Load Failure will be occurred, check the leak

point and do the test again.

(LDO)(LDO) 2.5MPa(LDO) 60S 2.5MPa

2. If the oil pressure after filling is normal, LDO supply oil shut-off valve is closed, and

then the oil pressure shall be checked for 180 second period. If the filling oil pressure falls

below than 20 bar, the message LDO burner oil valve Leak will be displayed, check the

leak point and do the test again.

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(LDO) 180 2.0MPa,

3. If the oil pressure is greater than 20 bar for more than 180 seconds, the logic will auto

open the LDO return oil shut-off valve to release the oil pressure in oil pipeline, and auto

close it after the oil pressure falls below 0.5 bar. After 90 seconds, if the LDO return oil

shut-off valve is not closed or oil pressure not lower than 0.5 bar then the message Oil

Unload Failure will be displayed.

(LDO) 180S 2.0MPa 90

4. If the LDO return oil shut-off valve closed after successful oil unloads, then start the

oil pressure check within a 120 seconds period. If the oil pressure becomes greater than 2

bar, the logic will send the message LDO supply oil shut-off valve Leak.

120 0.2Mpa

5. If no any oil leak or failure signal occurs during the all LDO oil leak test procedure, the

message LDO Oil Leak Test successes will be displayed on station LCD. The total LDO

oil leak test will be completed in about 450 second, and the test countdown timer will be

displayed also.

450s

During the LDO oil leak test, any of the following conditions will cancel the test procedure:

MFT trip pulse MFT

MFT reset pulse MFT

Fill Oil Failure pulse

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LDO burner oil valve leak pulse

LDO supply oil shut-off valve leak pulse

LDO oil Unload failure pulse

LDO oil Leak test success pulse

LDO Oil Leak Test success signal will be reset under any of the following conditions:

MFT trip pulse MFT

LDO oil Leak Test in Progress pulse

5.2.2. HFO Leak Test Procedure HFO

The HFO have the similar Leak test procedure with the LDO test procedure.

The following is the HFO leak test permissive conditions:

(HFO)

MFT activated, or LDO layer in service or any coal layer is in service [MFT ][ MFT ]

HFO supply oil shut-off valve closed

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All HFO burner oil valves closed (HFO)

HFO supply pressure normal

After all the conditions has been satisfied, the message HFO Leak Test Permit will be

displayed on station LCD, operator can push the button labeled with start HFO Leak Test

on LCD to start the test. When the test demand output, the logic will close HFO return

header shut-off valve, send the bypass command to MFT hardwired trip relay for HFO

supply shut-off valve, open the HFO supply shut-off valve and HFO supply oil pressure

adjust CV and the message HFO Oil Leak Test in Progress will be displayed on station

LCD. The following procedure will be started:

CRT (HFO) CRT

(HFO)(HFO)(HFO)

CRT 1. Opening of HFO supply oil shut-off valve to fill the oil into header pipeline, it will be

closed after 60 second when the oil pressure before the HFO return valve is greater

than 25 bar. If the filling oil pressure could not reach25bar during 60 second after the

supply shut-off valve opened, the message Fill Oil Failure will be occurred, check the

leak point and do the test again.

(HFO)(HFO) 2.5MPa(HFO) 60S 2.5MPa

2. If the oil pressure after filling is normal, HFO supply oil shut-off valve will be closed,

and then the oil pressure shall be checked for 180 seconds. If the filling oil pressure falls

below than 20 bar, the message HFO burner oil valve Leak will be displayed, check

the leak point and do the test again. (HFO)1802.0MPa,

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3. If the oil pressure is greater than 20 bar for more than 180 seconds, the logic will

auto open the HFO return oil shut-off valve to release the oil pressure in oil pipeline, and

auto close it after the oil pressure falls below 0.5 bar. After 90 seconds, if the HFO

return oil shut-off valve is not closed or oil pressure not lower than 0.5 bar then the

message Oil Unload Failure will be displayed

(HFO) 180S 2.0MPa 90

4. If the HFO return oil shut-off valve is closed after successful oil unloads, then start

the oil pressure check within a 120 seconds period. If the oil pressure becomes greater

than 2 bar, the logic will send the message HFO supply oil shut-off valve Leak.

90 120 0.2Mpa

5. If no any oil leak or failure signal occurs during the all HFO oil leak test procedure,

the message HFO Oil Leak Test successes will be displayed on station LCD. The total

HFO oil leak test will be completed in about 450 seconds, and the test countdown timer

will be displayed also.

450s

During the HFO oil leak test, any of the following conditions will cancel the test procedure:

(HFO)

MFT trip pulse MFT

MFT reset pulse MFT

Fill Oil Failure pulse

HFO burner oil valve leak pulse

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HFO supply oil shut-off valve leak pulse

HFO Oil Unload failure pulse

HFO Oil Leak test success pulse

HFO Oil Leak Test success signal will be reset under any of the following conditions:

(HFO)

MFT trip pulse MFT

HFO Oil Leak Test in Progress pulse

5.3. Furnace Purge

As per the basic rules of NFPA85, furnace must be purged with proper air flow rate for a

predefined time before any fuel enters the furnace. Excess combustible matters may be

accumulated at the boiler convection pass, flue pass, and the induced draft fans which is

used for transfer flue gas to chimney. If these combustible matters mixed with proper air

rate and meet the ignition energy source that may lead to the boiler explosion. Hence

boiler purging is required after every MFT before the boiler start up.

The purpose of furnace purge is to clean the residues combustible matters to prevent the

deflagration during boiler ignition.

NFPA85

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MFT

5.3.1. Furnace Purge Permissive Conditions The following conditions must be satisfied for the furnace purge cycle:

Primary furnace purge condition lists are as below:

()

MFT activate MFT

All burner oil valves and its purge valves, atomizing steam/air valves are closed

All pulverizers stopped

All coal feeders stopped

All pulverizer outlet dampers closed

All Primary Air Fan stopped

Any Air Pre Heater running

Any Induced Draft Fan running

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Any Forced Draft Fan running

No any MFT conditions exist MFT

No any flame detected in furnace (All flame Scanners shows no flame)

Secondary furnace purge conditions list as below:

total air flow rate between 30% and 40% 30%--40%

Boiler drum level normal (between -150mm and 150mm) -150mm---150mm

Furnace pressure normal (between -300Pa and 300Pa) (-300Pa300Pa)

Fuel oil leak test success or test bypassed

SOFA air damper closed SOFA

Swaying burner tilt position horizontal

5.3.2. Furnace Purge Procedure After MFT occurs, the Furnace Purge Required will be generated, and if all primary purge

conditions are satisfied, the message Purge Ready will be displayed on LCD. Then

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operator can push the button labeled with Start Purge to start the furnace purge

procedure.

MFT CRT

The logic will auto start the LDO/HFO fuel oil leak test and set the auxiliary air dampers to

the purge position first after receiving the start command, then it will wait for the secondary

purge conditions becomes true, and when all purge permissions satisfied the furnace

purge start actually. The message Furnace Purge in Progress will be displayed on LCD,

purge countdown timer will also be started. The purge time is 300 second as predefined.

CRT 300

In order to purge the furnace completely and cleanly, the purge procedure must be lasted

300 seconds with between 30% and 40% rated total air flow rate.

30-40% 5

During purge process, FSSS logic will continuously supervise all the primary and

secondary purge conditions. The primary purge conditions are the necessary condition for

FSSS goes into purge mode; and the secondary purge conditions will start the purge

timer.

FSSS

FSSS

If the secondary purge conditions (e.g. total air flow less than 30%) are not satisfied during

purge process, the purge timer will be reset. But the purge procedure not exit, and the

message Purge Interrupt will be blinking displayed on LCD. After the secondary purge

conditions are satisfied again, the purge timer will be started once more.

If the primary purge conditions are not satisfied during the purge process, the purge

procedure will be stopped and FSSS exit the purge mode, the purge timer will be reset

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simultaneous. If not in purge mode, the operator needs to start the purge procedure

manually again.

>30

If the purge procedure lasts for 300 seconds and all purge conditions are satisfied, the

message Purge Complete will displayed on LCD.

5 CRT

Furnace purge complete signal is the necessary condition for MFT reset.

MFT The MFT pulse will clear the Purge Complete signal.

MFT MFT

5.4. Oil Fuel Ignition condition

5.4.1. LDO Ignition Conditions LDO The following conditions must be all satisfied to permit the LDO ignition:

(LDO)

MFT reset MFT

LDO OFT reset (LDO)OFT

LDO supply shut-off valve opened

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Flame detector cooling air pressure normal

Instrument air pressure normal

Boiler drum level normal

Furnace pressure normal

5.4.2. HFO Ignition Conditions HFO The following conditions must be all satisfied to permit the HFO ignition:

(HFO)

MFT reset MFT

HFO OFT reset (HFO)OFT

HFO supply shut-off valve opened

Flame detector cooling air pressure normal

Atomizing steam pressure normal

Atomizing steam temperature normal

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HFO supply oil temperature normal

Any oi lay running or any coal layer running BC/EF



5.5. Oil Shutoff Valve logic

After the successful fuel oil leak test, FSSS will auto reset the OFT and then operator can

open the supply oil shut-off valve.

FSSSOFT.

If OFT is there, FSSS will auto close the supply oil shut-off valve.

OFT

During fuel oil leak test process, FSSS will override open the supply oil shut-off valve, and

close it when the filling oil pressure reaches the predefined value.

5.5.1. LDO Supply Oil Shut-off Valve LDO The following is the open permissive conditions (and):

LDO burner oil valve closed LDO supply oil Pressure Normal

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LDO leak test in progress or Leak test OK The following is the auto open condition:

LDO leak test start command The following is the auto close conditions (or):

LDO leak test close the supply shut-off valve command LDO OFT and not in LDO leak test Fill oil failure during LDO leak test

(LDO) (LDO)

(LDO)

(LDO)(LDO) (LDO)(LDO)OFT

5.5.2. HFO Supply Oil Shut-off Valve HFO The following is the open permissive conditions (and):

HFO burner oil valve closed HFO Supply oil pressure normal HFO leak test in progress or HFO leak test ok

The following is the auto open condition:

HFO leak test start command

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The following is the auto close conditions (or):

HFO leak test close the supply shut-off valve command HFO OFT and not in LDO leak test Fill oil failure during LDO leak test

(HFO) (HFO)

(HFO)

(HFO)(HFO) (HFO)(HFO)OFT

5.5.3. LDO Return Oil Shut-off Valve LDO The following is the auto open condition:

LDO leak test open the return shut-off valve command The following is the auto close conditions (or):

LDO leak test start command LDO leak test unload oil command MFT

(LDO)

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(LDO) (LDO) MFT

5.5.4. HFO Return Oil Shut-off Valve HFO The following is the auto open condition:

HFO leak test open the return shut-off valve command The following is the auto close conditions (or):

HFO leak test start command HFO leak test unload oil command MFT

z (HFO)

z (HFO)

z (HFO)

z MFT

5.6. Flame Detector Cooling Air Fan

The flame detector probes are mounted around the furnace burners. Its very important to

keep the flame detector probes cooled and cleaning, the high temperature will reduce the

flame detector working stability and life.

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The flame detector cooling air fan can provide the sufficient cooling air flow to make the

probe working normally. The unit contains two probe cooling air fans to provide cooling air

for flame detector probes. In general, one is in service and the other is in stand by. When

the running air fan tripped or the outlet pressure is not sufficient, the standby fan will be

auto started by logic

5.6.1. Flame Detector Cooling Air Fan A A If all the following conditions are satisfied, the operator can put the cooling air fan A in

standby status by pressing the button labeled with STBY on station LCD, or by pressing

the button on local control panel:

A

Cooling air fan A not running and Cooling air fan B running A

Any of the following conditions will reset the cooling air fan A in standby

Operator press the release button labeled with STBY on LCD A

The cooling air fan A is running A

The following is the cooling air fan A logic:

Auto start condition (or):

The cooling air fan B protection trip when fan A is in standby

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Any of the flame detector air head pressure low when fan A is in standby Stop permissive condition (or):

The cooling air fan B running and head pressure not low with 20s delay MFT occurs with 2 hours delay

z A B

z A

z B 20

z MFT 2

5.6.2. Flame Detector Cooling Air Fan B B The flame detector cooling air fan B has the similar logic that of fan A.

A AB BA

6. FUEL OIL CONTROL LOGIC

6.1. LDO Control Logic

Boiler can be ignited only after the furnace purge completed and all LDO ignition

permissive conditions are satisfied. LDO burner can be ignited by the high-energy arc

ignitor, any other ignition energy source like coal burners flame is not permitted.

The LDO control logic includes LDO layer control, coupling control, and single control.

(LDO)(LDO)

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LDO burner system includes two layers, this document only describes the LDO BC burner,

and LDC EF burners have the similar logic.

LDO BCEF BC EF

6.1.1. LDO Layer Control(e.g. BC) ( BC ) The BC oil layer will be start under any of the following conditions effect:

BC

Operator start the BC oil layer BC

RB start the BC oil layer RB

When the BC oil layer received start command, FSSS logic will auto start the BC oil layer

with the sequence of BC1, BC3, BC2, and BC4 oil gun with 10 seconds interval. The

signal BC layer start complete will be sent after BC1, BC2, BC3, and BC4 oil gun running

normally.

BCFSSSBC1BC3BC2BC4BC10sBC1BC3BC2BC42sBC

The BC oil layer start command will be reset under any of the following conditions:

BC

MFT MFT

OFT OFT

BC layer start complete pulse BC

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BC layer stop demand

The following condition will stop the BC oil layer:

BC

Operator stop the BC oil layer BC

When the BC oil layer receives stop command from the operator, FSSS logic will auto stop

the BC oil layer with the sequence of BC1, BC3, BC2, and BC4 oil gun with 5 seconds

interval. The signal BC layer stop complete will be sent after BC1, BC2, BC3, and BC4

oil gun stopped with 2 second on delay.

BCFSSSBC1BC3BC2BC4BC5SBC1BC3BC2BC42sBC

BC oil layer in service signal will be established when three of four BC layer burners are

running.

BC3BC

6.1.2. LDO Coupling Control LDO coupling control have the similar logic with layer control, the difference is only start

(stop) the BC1/BC3 or BC2/BC4 oil guns when LDO coupling control logic received the

start (stop) command.

/ 13 24

6.1.3. LDO Single Control (e.g. BC1) LDO BC1

This document only describes the LDO BC1 burner; other LDO burners have the similar

logic.

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The following conditions are LDO BC1 burner start permissive conditions:

BC1(LDO)

LDO ignition permissive condition exists (LDO)

BC1 burner oil valve closed BC1

No BC1 burner trip condition exists BC1 (LDO)

Initial ignition permissive condition exists

BC1 burner ignition system in remote BC1

Initial ignition permit condition is explained in detail below:

If the first LDO oil gun ignition failed, FSSS logic will start the 1 minute post purge to

ensure that no combustible matters will be accumulated in furnace. So the Initial ignition

permit condition will lose when any of the oil guns ignites failed to disable the oil gun start

during the FSSS in purge process. After 1 minute Initial ignition permit condition will

occurs again. If any oil gun is running in furnace normally, the Initial ignites permit

condition will always exist.

FSSS logic permit two times of oil gun ignition failure and the third oil gun ignition failure

will activate the MFT.

(LDO)FSSS1111MFT

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With the LDO BC1 burner start permissive conditions, any of the following command will

start the BC1 burner:

BC1(LDO)BC1

Operator Manual start command

LDO layer start command

LDO BC1/BC3 coupling start command

Operator Manual start command in local

The following is the BC1 burner start sequence:

BC1

1. Extend the oil gun

2. Opening the oil gun purge valve and closure of it after 10 seconds later. (No this

pre-purge process if RB start this oil gun)

10sRB

3. Extend the high-energy arc ignitor and spark

4. Opening the burner oil valve

5. After the burner oil valve opening, if the BC1 flame can be detected during 10

seconds then the ignitor sparking is stopped and retracted. Oil gun running successfully.

10 s

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BC1 burner flame on signal will be established if all of the following conditions exist:

BC1

BC1 flame detected BC1

BC1 oil valve opened BC1

BC1 burner in service signal will be established if all of the following conditions exist:

BC1

BC1 flame detected BC1

BC1 oil valve opened BC1

BC1 purge valve closed BC1

BC1 oil gun extended BC1

Note: If no flame detected during 10 seconds after oil valve is opened, logic will consider

ignition failure, this is the burner failure and will close the oil valve immediately. At this time,

if no MFT occurs the logic will open the purge valve to start the post-purge process, and

retract the oil gun when purge complete; but if MFT/OFT occurs on burner failure the logic

will directly retract the oil gun, stop the high-energy arc ignitor sparking and retract it.

10sMFTMFT

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The following is the BC1 burner stop sequence:

BC1(LDO):

1. Closure the burner oil valve

2. Extend the high-energy arc ignitor and sparking for 10 seconds, after 10 seconds will

be retracted. But if any coal layer is running at the same time, the high-energy arc ignitor

will not be extended.

[10S][]

3. Opening of the purge valve

4. The oil gun purge process shall be started within 60 seconds.

60s

5. Closing of the purge valve, the oil gun will be retracted.

BC1 oil burner stop signal will be generated if any of the following conditions exists

BC1:

LDO layer stop, or LDO BC1/BC3 coupling stop, or operator manual stop BCBC1

MFT MFT

LDO OFT OFT

BC1 oil gun still not extended after BC1 burner in fire mode after 8 seconds BC1/8sBC1

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BC1 oil valve not opened after oil gun has extended with time delay of 30 seconds when burner in fire mode.

BC1/BC130sBC1

BC1 flame no detected after BC1 oil valve opened with time delay of 10 seconds BC110sBC1

BC1 purge valve not closed when BC1 burner in service BC1BC1

BC1 oil burner stop signal will reset the BC1 burner in fire mode. BC1 oil gun extended

pulse signal will auto reset the BC1 oil burner stop signal

BC1BC1/BC1BC1

If BC1 oil burner stop signal occurs, FSSS logic will close the BC1 oil valve, and stop the

BC1 burner as per the BC1 burner stop sequence.

BC1FSSSBC1BC1

The following is the BC1 purge requirement condition (or):

BC1

BC1 oil valve closed pulse BC1

BC1 burner start command pulse BC1

Any of the following conditions will reset purge requirement (or):

BC1

MFT MFT

BC1 burner oil gun retracted BC1(LDO)

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BC1 burner purge complete BC1

BC1 oil gun extend fail pulse BC1(LDO)

BC1 purge requirement overtime. BC1

6.2. HFO Control Logic

HFO burner system includes three layers, this document only describes the HFO AB1

burner, and others HFO burners have the similar logic.

The HFO control logic includes HFO layer control, coupling control, and single control.

AB1

6.2.1. HFO Layer Control (e.g. AB) HFOAB AB oil layer will be start under on any of the following conditions

AB

Operator start the AB oil layer AB

When the AB oil layer receives start command, FSSS logic will auto start the BC oil layer

with the sequence of AB1, AB3, AB2, and AB4 oil gun with 10 seconds interval. The signal

AB layer start complete will be sent after AB1, AB2, AB3, and AB4 oil gun running

normally.

ABFSSSAB1AB3AB2AB4AB10sAB1AB3AB2AB42sAB

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AB oil layer start command will be reset under any of the following conditions

AB

MFT MFT

HFO OFT OFT

AB layer start complete pulse AB

AB layer stop demand AB

AB oil layer will be stopped under the following condition

AB

Operator stop the AB oil layer AB

When the AB oil layer receives stop command from the operator, FSSS logic will auto stop

the AB oil layer with the sequence of AB1, AB3, AB2, and AB4 oil gun with 5 seconds

interval. The signal AB layer stop complete will be sent after AB1, AB2, AB3, and AB4 oil

gun stopped with 2 second on delay.

ABFSSSAB1AB3AB2AB4AB5SAB1AB3AB2AB42sAB

AB oil layer in service signal will be established when three of four AB layer burner are

running.

AB3AB

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6.2.2. HFO Coupling Control HFO coupling control have the similarly logic with layer control, the difference is only start

(stop) the AB1/AB3 or AB2/AB4 oil guns when HFO coupling control logic receives the

start (stop) command.

/ 13 24

6.2.3. HFO Single Control (e.g. AB1) HFO AB1

This document only describes the HFO AB1 burner, other HFO burners have the similar

logic.

AB1(HFO)

The following conditions are HFO AB1 burner start permissive conditions:

AB1(HFO)

HFO ignition permissive condition exist (HFO)

AB1 burner oil valve closed AB1

No AB1 flame detection AB1

No AB1 burner trip condition exist AB1(HFO)

AB1 burner not lost the valve power AB1

With the HFO AB1 burner start permissive conditions, any of the following command will

start the AB1 burner:

AB1(HFO)AB1

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Operator Manual start command

HFO AB layer start command

HFO AB1/AB3 coupling start command

Operator Manual start command in local

The following is the AB1 burner start sequence:

AB1

1. Extension of the oil gun

2. Opening of the oil gun purge valve and it is closed after 30 seconds. (No this

pre-purge step if RB start this oil gun)

30sRB

3. Extension the high-energy arc ignitor (10HHY61IV001) and spark

4. Opening of the burner oil valve and atomizing valve

5. After the burner oil valve opened, if the AB1 flame can be detected during 10 seconds

then the ignitor sparking is stopped and retracted. Oil gun running successfully.

10s

AB1 burner flame on signal will be established if all the following conditions exist:

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AB1

AB1 flame detected AB1

AB1 oil valve opened AB1

AB1 burner in service signal will be established if all the following conditions exist:

AB1

AB1 flame detected AB1

AB1 oil valve opened AB1

AB1 purge valve closed AB1

AB1 oil gun extended AB1

AB1 atomizing valve opened AB1

Note: If no flame is detected during 10 seconds after oil valve is opened, logic will consider

ignition failure, this is the burner failure and will close the oil valve immediately. At this time,

if no MFT occurs the logic will open the purge valve to start the post-purge process, and

the oil gun will be retracted when purge complete; but if MFT occurs when burner failure

the logic will directly retract the oil gun, the high-energy arc ignitor sparking is stopped and

retracted.

10s,MFT MFT

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The following is the AB1 burner stop sequence:

AB1(HFO):

1. Closing of the burner oil valve, closing of the atomizing valve

2. Extension of the high-energy arc ignitor and sparking with 10 seconds, after 10

seconds it will be retracted . But if any coal layer is running at the same time, the

high-energy arc ignitor will no need to extend.

[10S][]

3. Opening the purge valve

4. Starting the oil gun purge process within 60 seconds.

60s

5. Closing the purge valve and retraction of the oil gun.

AB1 oil burner will be stopped under any of the following conditions effect:

AB1

HFO layer stop, or HFO AB1/AB3 coupling stop, or operator manual stop ABAB1

MFT MFT

HFO OFT OFT

AB1 oil gun still not extended after AB1 burner in fire mode with 8 seconds delay.

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AB1 / 8s AB1

AB1 oil valve not opened after oil gun has extended with 50 seconds delay when burner in fire mode.

AB1 /AB1 50sAB1

AB1 flame not detected after AB1 oil valve opened with 10 seconds delay AB1 10s AB1

AB1 atomizing valve not opened when burner in fire mode. AB1 /BC1

AB1 purge valve not closed or atomizing valve not opened when AB1 burner in service AB1 BC1

AB1 oil burner stop signal will reset the AB1 burner in fire mode. AB1 oil gun extended

pulse signal will auto reset the AB1 oil burner stop signal

AB1AB1/AB1AB1

If AB1 oil burner stop signal occurs, FSSS logic will close the AB1 oil valve, and stop the

AB1 burner as per the AB1 burner stop sequence.

AB1FSSSAB1AB1

The following is the AB1 purge requirement condition (or):

AB1

AB1 oil valve closed pulse AB1

AB1 burner start command pulse AB1

The following conditions will reset purge requirement (or):

AB1

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MFT MFT

AB1 burner oil gun retracted AB1(HFO)

AB1 burner purge complete AB1

AB1 oil gun extend fail pulse B1(HFO)

AB1 purge requirement overtime. AB1

7. COAL-FIRED CONTROL LOGIC Coal-fired control logic accomplishes the pulverizer system start/stop control, supervision

of every running coal layer parameters, and fast cut off the coal if necessary to ensure

the furnace in safety condition.

7.1. Coal Ignition Condition

All the following conditions must be satisfied for the coal burner ignition:

MFT reset MFT

The differential pressure of furnace and secondary air wind box is normal

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The differential pressure of furnace and hot primary air header not low

Hot secondary air temperature > 160 160

Any Primary air fan running

Swaying burner tilt position horizontal or any coal layer in service



7.2. Coal Layer Ignition Energy Requirement

Any of the following conditions satisfied means coal layer A ignition energy is sufficient

A A

AB oil layer in service AB

Coal layer B RUN under boiler load > 30% 30%B

Any two Coal layers in service under boiler load > 60% 60%

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Any of the following conditions satisfied means coal Layer B ignition energy is sufficient

B

AB oil layer in service AB

BC oil layer in service BC

Coal layer A RUN under boiler load > 30% 30%A

Coal layer C RUN under boiler load > 30% 30%C


Any of the following conditions satisfied means coal Layer C ignition energy is sufficient:

C

BC oil layer in service BC

CD oil layer in service CD

Coal layer B federate > 50% RUN under boiler load > 30% 30%B 50%

Coal layer D federate > 50% RUN under boiler load > 30% 30%D 50%


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Any of the following conditions satisfied means coal Layer D ignition energy is sufficient

D

CD layer oil layer in service CD

Coal layer C federate > 50% RUN under boiler load > 30% 30%C 50%

Coal layer E federate > 50% RUN under boiler load > 30% 30%E 50%


Any of the following conditions satisfied means coal Layer E ignition energy is sufficient

E

EF oil layer in service EF

Coal layer D federate > 50% RUN under boiler load > 30% 30%D 50%

Coal layer F federate > 50% RUN under boiler load > 30% 30%F 50%


Any of the following conditions satisfied means coal Layer F ignition energy is sufficient

F

EF oil layer in service EF

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FG oil layer in service FG

Coal layer E federate > 50% RUN under boiler load > 30% 30%E 50%

Coal layer G federate > 50% RUN under boiler load > 30% 30%G 50%


G

FG oil layer in service FG

Coal layer F federate > 50% RUN under boiler load > 30% 30%F 50%


Coal Layer A in service will be established if all the following conditions are satisfied.

A

Pulverizer A running A

Coal feeder A have been running for 1 minute A

At least three flame detected of the corner A1, A2, A3, A4 A 3/4

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Burner A1 in service will be established under all the following conditions effect.

A1

Pulverizer A running A

Coal feeder A have been running 1 minute A

Corner A1 flame detected A1

After coal layer ignition energy is established, operator can start the total coal layer.

The Coal layer ignition condition is suitable for all coal layers, and any coal layer will be

inhibited to start if this condition is not satisfied.

7.3. Coal Layer Sequence Control

7.3.1. Coal Layer A Sequence start procedure A 1. Start the pulverizer A lube oil pump

A

2. Open the pulverizer A sealing air damp, close pulverizer A inlet hot air damp

A ,

3. Open the pulverizer A outlet damps

A

4. Open the pulverizer A inlet cold air damp,

A

5. pulverizer A purge process 60s

A 60

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6. Start the pulverizer A and separator under the pulverizer A start condition occurs.

A A

7. Open the pulverizer A inlet hot air damp nd set the modulated air damps to default

pulverizer warm position

A

8. Open the coal feeder A sealing air damp aOpen the coal feeder A outlet valve and set feeder min rate

A

9. Start the coal feeder A under the temperature of pulverizer A above 65

A 65

10. Open the coal feeder A inlet valve

A

7.3.2. Coal Layer A Sequence stop procedure A 1. Request CCS to set the coal feeder A feedrate to minimum

CCS A

2. Set pulverizer A outlet temperature 65,

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A

6. Stop the pulverizer A and separator after the coal feeder A outlet valve has been

closed 5 minutes

A 5

7. Close the pulverizer A inlet hot air damp and set the modulated inlet cooling air

damp to cooling position

8. Close the pulverizer A outlet damp 3/4

4 3

9. Cooling pulverizer A process 320s

320

10. Close the pulverizer A inlet cooling air damp&release oil pump stby

11. Close outlet damp 1/4 and stop lube oil pump

7.4. Pulverizer Lube Oil Pump

In this project, all pulverizers have two lube oil pumps and only one is running during

normal condition, so the standby logic is designed.

This document only describes the pulverizer A lube oil pump A logic.

The following is the start permissive conditions (and):

Pulverizer A lube oil station oil temperature >25 Pulverizer A lube oil station oil level not low

The following is the stop permissive conditions (or):

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Pulverizer A has been stopped for 120 seconds Pulverizer A lube oil pump B running

Occurrence of any of the following conditions will auto start the pump A if pump A in

standby:

Pulverizer A lube oil pump B tripped Pulverizer A lube oil pressure low Pulverizer A lube oil flow low

The following is the auto stop condition (or):

Pulverizer A lube oil station oil pressure has been low for 120 seconds Pulverizer A lube oil temperature >65 for more than 120 seconds

A A

A 25 A

A 120s A B

A B A A

A 120s A 65 120s

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7.5. Pulverizer Lube Oil Box Heater A

This document only describes the pulverizer A lube oil box heater logic.

The following is the start permission:

Pulverizer A lube oil station oil level not low The following is the auto start condition:

Pulverizer A lube oil station oil temperature 40 A

A

A 35

A 40

7.6. Pulverizer A A

7.6.1. Pulverizer A Trip Condition A Coal layer A trip will be set if any of the following conditions available:

A

Operator trip command A

MFT exist

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MFT

Both pulverizer sealing air fan stopped with 10 seconds delay 10s

Both primary air fan stopped

The diff pressure of pulverizer A inlet PA and sealing air low(1.25kPa) with 60 second delay

A 60s

The primary air pressure low6.2kpa and feeder a running with 2 seconds delay 6.2kpa 2s

Lost the Coal layer A flame trip. The Coal layer A flame is established by three of four burner flam detected.

3/4A

Lost pulverizer A ignition energy A

Lube oil trip will generated under the following conditions effect:

a) Pulverizer A lube oil pump both not running

A

b) Pulverizer A lube oil pressure very low0.7barwith 2 seconds on delay

A2s

c) Pulverizer A lube oil temperature > 65 with 15 seconds on delay

A65,15s

Pulverizer A outlet damp two of four closed under pulverizer A is running

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A2

Pulverizer A bearing temperature high(>85,90,95) A(>85,90,95)

Pulverizer motor wingding temperatures high(>130). A(>130)

RB command (only effect to coal layer GF, E, and D) RBGFED

7.6.2. Pulverizer A Start permission A The following conditions are the permissive conditions for pulverizer start up:

A

Mill outl temperature between 70 and 85 70~85

Pulverizer A inlet cold air damper opened A

Pulverizer A all outlet damper opened A

Pulverizer A sealing air damper opened A

Pulverizer A fire-extinction steam valve closed A

Pulverizer A rejecting outlet valve open A

Coal A layer no flame detected

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A

Coal layer ignition condition exist

Coal layer A ignition energy satisfied A

Pulverizer A bearing temperature OK(160L/min)

A(>160L/min)

c) Pulverizer A lube oil pressure >0.9bar with 3 minutes delay

A>0.9bar3min

d) Pulverizer A lube oil filter diff pressure not high

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A

The following condition is pulverizer A stop permission:

7.7. Coal Feeder A A

The following conditions are the permissive conditions for feeder start up:

Pulverizer A is running Coal feeder A sealing air damp opened Coal feeder A outlet valve opened Coal feeder A outlet temperature not high Coal feeder A outlet not block Coal feeder A outlet valve opened Pulverizer A Primary air flow normal No any coal layer A trip conditions exist

Coal feeder A will auto stop under the following conditions effect:

Pulverizer A stopped under coal feeder A running Any pulverizer A trip condition Coal feeder A outlet valve closed with 5 seconds delay Coal feeder A outlet blockage with 20 seconds delay Coal feeder A belt zero coal with 5 seconds delay Coal feeder A inner over temperature with 3 seconds delay

A A A

DCS FSSS WRITE UP





A A A A A

A A A 5s A 20s A 60s 5s

7.8. Pulverizer A Inlet Cold Air Damper A

The following is the open permission:

Pulverizer A outlet damper opened The following is the close permission:

Pulverizer A not running & outlet temperature < 60 The following is the auto close condition:

MFT occurs Any pulverizer trip conditions occurs

A

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A

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MFT exist Pulverizer A trip condition exist

A

A

MFT A

7.11. Pulverizer A Sealing Air Damp A

The following is the close permission:

Pulverizer A stopped A

The following is the auto close condition:

Pulverizer A stopped with 60s delay A 60

7.12. Pulverizer A Inerting Steam Inlet Valve A

DCS FSSS WRITE UP





Manually control.

7.13. Coal Feeder A Inlet Valve A


Coal Feeder A tripped

A

7.14. Coal Feeder A Outlet Valve


Coal Feeder A stopped The following is the auto close condition:

Pulverizer A stopped pulse Coal Feeder A outlet temperature high

A

A A

7.15. Coal Feeder A Sealing air Damp A


Coal feeder A stopped

DCS FSSS WRITE UP





A


Coal feeder A stopped with 60s delay A 60

7.16. Run Back

Run Back (RB) is a function initiated by CCS system when the boiler could not operate

with the set load due to the failure of major auxiliary device of the boiler such as water

feed pump, forced/induced air fan, primary air fan,boiler water cycle water pump etc. in

case the unit load is above 50%. The purpose of RB function is to reduce the input fuel

fast and keep the boiler in safe operating condition.

Run BackRB 50%CCS

For the detailed RB conditions please refer the KSK DCS CLCS Write Up

RB DCS CLCS

FSSS system will perform the RB action only when more than three coal layers are in

service; the logic will remove the upper coal layers in service from top to bottom

preferentially in proper time interval to match the boiler load and the boiler auxiliary

devices contribution.

FSSS RB

7.16.1. Actions after RB When more than three coal layers are in service, if FSSS received the RB command, the

following will be performed:

DCS FSSS WRITE UP





FSSS RB :

Fast start the LDO BC oil layer BC

Remove coal layer G, F E and D from top to bottom layer. Coal layer G will be shutdown first. Coal layer FE will be shutdown if still more than three coal layers are in service at the moment 5 seconds adjustable after coal layer D shutdown. The process will

continue in that way until coal layer A is shutdown.

G F EAGG5F D

7.16.2. RB Reset Condition RB The following conditions will reset the RB signal (or):

RB

MFT MFT

Only when three or less than three coal layers still in service with predefined times delay.

KMPCL_6í-600MW_DCS_FSSS_Writeup_R1.1

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Transcript of KMPCL_6í-600MW_DCS_FSSS_Writeup_R1.1